TY - JOUR
T1 - ATHB4 and HAT3, two class II HD-ZIP transcription factors, control leaf development in Arabidopsis
AU - Bou-Torrent, Jordi
AU - Salla-Martret, Mercè
AU - Brandt, Ronny
AU - Musielak, Thomas
AU - Palauqui, Jean Christophe
AU - Martínez-García, Jaime F.
AU - Wenkel, Stephan
PY - 2012/1/1
Y1 - 2012/1/1
N2 - In response to plant proximity or canopy shade, plants can react by altering elongation growth and development. Several members of the class II homeodomain-leucine zipper (HD-ZIPII) transcription factor family have been shown to play an instrumental role in the responses to shade. HD-ZIP members of the class III (HD-ZIPIII), by contrast, are involved in basic patterning processes. We recently showed that REVOLUTA (REV), a member of the HD-ZIPIII family, directly and positively regulates the expression of several genes involved in shade-induced growth, such as those encoding HDZIPII factors HAT 2, HAT 3, ATH B2/HAT 4 and ATH B4, and of the components of the auxin biosynthesis pathway YUCCA5 and TAA1. Furthermore, we could demonstrate a novel role for HD-ZIPIII in shade-induced promotion of growth. Here we show that besides responding to shade, ATHB4 and HAT3 have a critical role in establishing the dorso-ventral axis in cotyledons and developing leaves. Loss-of-function mutations in these two HD-ZIPII genes (athb4 hat3) results in severely abaxialized, entirely radialized leaves. Conversely, overexpression of HAT3 results in adaxialized leaf development. Taken together, our findings unravel a so far unappreciated role for an HD-ZIPII /HD-ZIPIII module required for dorso-ventral patterning of leaves. The finding that HD-ZIPII /HD-ZIPIII also function in shade avoidance suggests that this module is at the nexus of patterning and growth promotion. © 2012 Landes Bioscience.
AB - In response to plant proximity or canopy shade, plants can react by altering elongation growth and development. Several members of the class II homeodomain-leucine zipper (HD-ZIPII) transcription factor family have been shown to play an instrumental role in the responses to shade. HD-ZIP members of the class III (HD-ZIPIII), by contrast, are involved in basic patterning processes. We recently showed that REVOLUTA (REV), a member of the HD-ZIPIII family, directly and positively regulates the expression of several genes involved in shade-induced growth, such as those encoding HDZIPII factors HAT 2, HAT 3, ATH B2/HAT 4 and ATH B4, and of the components of the auxin biosynthesis pathway YUCCA5 and TAA1. Furthermore, we could demonstrate a novel role for HD-ZIPIII in shade-induced promotion of growth. Here we show that besides responding to shade, ATHB4 and HAT3 have a critical role in establishing the dorso-ventral axis in cotyledons and developing leaves. Loss-of-function mutations in these two HD-ZIPII genes (athb4 hat3) results in severely abaxialized, entirely radialized leaves. Conversely, overexpression of HAT3 results in adaxialized leaf development. Taken together, our findings unravel a so far unappreciated role for an HD-ZIPII /HD-ZIPIII module required for dorso-ventral patterning of leaves. The finding that HD-ZIPII /HD-ZIPIII also function in shade avoidance suggests that this module is at the nexus of patterning and growth promotion. © 2012 Landes Bioscience.
KW - Arabidopsis thaliana
KW - Auxin
KW - HD-ZIPII
KW - HD-ZIPIII
KW - Leaf development
KW - Shade avoidance
U2 - 10.4161/psb.21824
DO - 10.4161/psb.21824
M3 - Article
SN - 1559-2316
VL - 7
JO - Plant Signaling and Behavior
JF - Plant Signaling and Behavior
IS - 11
ER -